I’m looking at going armv7 for my current project. I don’t have any iPhone 3GS generation hardware (which I believe is the earliest armv7), only older and newer. I’m wondering if I need to get one for base performance spec. I have read some suggestions the 3GS / iPod Touch 3rd gen are faster than iPhone 4 / iPod Touch 4th gen because they don’t have to render so many pixels, more than making up for the slower processor (same GPU).
Well here are some rough guidelines:
- draw calls are at least twice as fast on the 4g
- fill rate is at least twice as fast on the 3gs
- the 4g is roughly twice as fast at code execution
There is no such thing as “making up for the slower processor” since having a faster or slower cpu has no real bearing on gpu performance in an optimised environment (ie you’re using skinned/batched meshes, and capped by fill rate issues). However if you’re draw call limited then the faster cpu definately helps out. But there’s not the compensation you think since fill rate is the main problem, not cpu.
By twice, I mean the accuracy you would obtain by throwing a weighted doughnut from a fairground ride and pegging someone directly on their bald spot, who is on a different ride going at an entirely non complimentary trajectory. Get a test device or testers
Thanks hippocoder, when I said “making up for the slower processor”, I meant various forum posts suggest that the 3GS is less powerful, but it runs as fast, or faster, because it isn’t doing as much work because of the lower resolution. But as you say, the strengths are in different areas, so it looks like I will have to get a test device.